Error Bars Considered Harmful
Confidence intervals, standard error, and generalized error rates are
typically visualized with "error bars" - thin strokes that are superimposed over the mean. This work presents the results of crowdsourced experiments which illustrate that viewers misinterpret these
encodings even at the most basic level (where one would hope
larger margins of error reduce the confidence in judgments about
means). We then present evaluations of three alternate (or supplemental) visual encodings for the same task and show that choice of
visual encoding can result in viewers who make decisions which
are better informed by the margins of error.
Images and movies
BibTex references
@InProceedings{CG13, author = "Correll, Michael and Gleicher, Michael", title = "Error Bars Considered Harmful", booktitle = "IEEE Visualization Poster Proceedings", month = "oct", year = "2013", publisher = "IEEE", note = "to appear", url = "http://graphics.cs.wisc.edu/Papers/2013/CG13" }